Independent report

JCVI statement on COVID-19 vaccination of children and young people: 22 December 2021

Published 22 December 2021

Applies to England

Advice

Primary vaccination of 5 to 11 year olds

Children aged 5 to 11 years in a clinical risk group (as defined in the Green Book), or who are a household contact of someone who is immunosuppressed (as defined in the Green Book), should be offered two 10 micrograms doses of the Pfizer-BioNTech COVID-19 vaccine (Comirnaty®) with an interval of 8 weeks between the first and second doses. The minimum interval between any vaccine dose and recent COVID-19 infection should be 4 weeks.

Further advice regarding COVID-19 vaccination for other 5 to 11 year olds will be issued in due course following consideration of additional data. Data being sought includes:

  • updated estimates of the proportion of children aged 5 to 11 years who have already been infected
  • the level of protection afforded against COVID-19 disease due to the Omicron variant from previous SARS-CoV-2 infection
  • post-marketing adverse event reporting data from the international use of the Pfizer-BioNTech COVID-19 vaccine in those aged 5 to 11 years
  • considerations from the Department of Health and Social Care (DHSC) and other government departments on the potential educational impacts (both benefits and disbenefits) of COVID-19 vaccination in those aged 5 to 11 years

Booster vaccination of 12 to 17 year olds

The following cohorts of children and young people should be offered a booster dose of 30 micrograms Pfizer-BioNTech COVID-19 vaccine (Comirnaty®) no sooner than 3 months after completion of their primary course:

  • children and young people aged 16 to 17 years
  • children and young people aged 12 to 15 who are in a clinical risk group or who are a household contact of someone who is immunosuppressed
  • children and young people aged 12 to 15 years who are severely immunosuppressed and who have had a third primary dose

Prioritisation of booster vaccination within eligible cohorts should generally be in the order of descending age groups, or clinical risk, whichever is more expedient. Boosting of children in clinical risk groups should commence after the equivalent clinical risk adult groups; higher age is independently associated with a higher risk of complications from COVID-19 and these adults will have received their primary vaccinations earlier in the vaccine programme. 

Considerations

Primary vaccination of 5 to 11 year olds

When formulating advice in relation to childhood immunisations, JCVI has consistently held that the main focus of its considerations should be the potential benefits and harms of vaccination to children and young people themselves. The benefits and risks from COVID-19 vaccination in children and young people are finely balanced largely because the risks associated with SARS-CoV2 infection are very low. Of all age groups, children aged 5 to 11 years are those at lowest risks of serious COVID-19.[footnote 1]

JCVI has considered data on:

  • the risk of hospitalisation, paediatric intensive care unit (PICU) admission, mortality and paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) following SARS-CoV-2 infection

  • the effectiveness of COVID-19 vaccination in preventing infection, symptomatic disease, hospitalisation, intensive care admission and mortality, and the prevention of PIMS-TS and ‘long COVID’ through protection against infection and disease

  • the incidence and severity of suspected adverse events following vaccination including available data on the risk of myocarditis following vaccination

  • estimates of the proportion of 5 to 11 year olds with prior SARS-CoV-2 infection in the UK

  • a risk-benefit analysis undertaken by the UK Health Security Agency (UKHSA)

Vaccine safety and efficacy

In a clinical trial of 2268 children aged 5 to 11 years randomised to receive 2 doses of 10 micrograms Pfizer-BioNTech COVID-19 vaccine or placebo, the vaccine was found to be safe and immunogenic.[footnote 2]

Immune responses in vaccinated 5 to 11 year olds were at least as good as those measured in 15 to 25 year olds who received 30 micrograms of Pfizer-BioNTech COVID-19 vaccine. Vaccine efficacy against confirmed COVID-19 was noted to be 90.7%, although with considerable uncertainty in this estimate due to the relatively small numbers involved.  Adverse reactions due to vaccination were mainly low-grade local and systematic reactions lasting one to 2 days.

Compared to adults and older children studied in previous trials, children aged 5 to 11 years reported more injection-site redness (15 to 19% vs 5 to 7%) and local swelling (10 to 15% vs 5 to 8%), but less fever (3 to 7% vs 1 to 20%) and less chills (5 to 10% vs 6 to 42%). Children aged 5 to 11 years were just as likely as 12 to 15 year olds to experience swelling of local lymph glands (0.9% vs 0.8%). No cases of myocarditis were observed.

Initial safety data from programmatic use of COVID-19 vaccination in 5 to 11 year olds in the United States indicates no new or unexpected concerns. More data is expected to accrue over time as experience with vaccination of this age group of children increases internationally.

Seroprevalence in children and young people

Evidence from cohort studies alongside mathematical modelling indicates that a substantial proportion of children and young people have already been infected with SARS-CoV-2 during the course of the pandemic (range from around 50 to 80%). Based on studies conducted over the initial waves of the pandemic, immunity that develops upon recovery from infection (natural immunity) has been demonstrated to provide good protection against subsequent severe COVID-19 (severe re-infection) for at least to 6 months. The level of protection afforded by natural immunity against the Omicron variant is still to be determined.

Balance of risk and benefit

The potential benefits from vaccination were estimated according to the presence or absence of underlying health conditions that increase the risk of serious COVID-19. These estimates are sensitive to changes in the level of vaccine effectiveness and level of protection from natural immunity with respect to the Omicron variant. In general, lowered levels of vaccine effectiveness would lower the potential benefits from vaccination whilst lowered levels of protection from natural immunity would increase the relative benefit from vaccination in persons previously infected.

Table 1: estimated first dose impact in previously infected and non-infected persons with an underlying health condition that puts them at higher risk of serious COVID-19

Age Prevented death per million first vaccine doses Prevented PICU admissions per million first vaccine doses Prevented hospital admissions per million first vaccine doses Prevented PIMS-TS cases per million first vaccine doses
5 to 11 years - 105 1,265 16
0 to 17 years 14 - - -

Table 2: estimated 2 dose course impact in previously infected and non-infected persons with an underlying health condition that puts them at higher risk of serious COVID-19

Age Prevented death per million 2 dose vaccine courses Prevented PICU admissions per million 2 dose vaccine courses Prevented hospital admissions per million 2 dose vaccine courses Prevented PIMS-TS cases per million 2 dose vaccine courses
5 to 11 years - 113 1,354 29
0 to 17 years 15 - - -

Extremely rare reports of myocarditis (inflammation of the heart) have been reported in young people following vaccination with mRNA COVID-19 vaccines. In the UK, the MHRA Yellow Card reporting rate for suspected myocarditis in persons aged under 18 year olds was 11 per million doses (data as of 1 December 2021).

Global data suggests the reporting rate for myocarditis in 12 to 15 year olds is lower compared to 16 to 17 year olds. In the US, over 300,000 first doses of 10 micrograms of Pfizer-BioNTech COVID-19 vaccine have been given to 5 to 11 year olds with no reports of myocarditis noted (data to 26 November 2021).

At the current time, JCVI considers the balance of potential benefits and harms is in favour of offering vaccination to children aged 5 to 11 years who are in a clinical risk group. Children aged 5 to 11 year old who are not in a clinical risk group but are household contacts of a immunosuppressed individual (of any age) should also be offered COVID-19 vaccination on the understanding that the main indication for vaccination is to indirectly increase protection of the person who is immunosuppressed. 

Vaccine dose

For children aged 5 to 11 years, a 10-microgram dose of Pfizer-BioNTech (Comirnaty®) vaccine for both the first and second doses is considered appropriate. This can be either as a paediatric formulated dose (10-microgram) or a fractional adult dose (one third of the adult 30 microgram dose). Should fractionated adult doses be offered, healthcare providers should have the necessary skills to deliver such fractional doses, with appropriate guidance, training and systems in place to support vaccine delivery.

A dose interval of 8 weeks between doses is advised; a longer dose interval  improves the immune response to the second dose, [footnote 3] and may reduce the risk of myocarditis,[footnote 4] compared with a shorter interval.

In all instances, the offer of vaccination must be accompanied by appropriate information to enable children, and those with parental responsibility, to provide informed consent prior to vaccination. UKHSA produces leaflets for children and parents on COVID-19 vaccines, including information on the risk of myocarditis.

Teams responsible for the implementation and deployment of COVID-19 vaccination for persons aged 5 to 11 years should be appropriately trained and confident regarding the information relevant to the vaccination of these persons. 

Booster vaccination of 12 to 17 year olds

On 29 Nov 2021, JCVI provided advice on immediate response measures within the COVID-19 programme to the emerging threat from the Omicron variant. A key purpose of those measures is the acceleration of the booster programme in order to mitigate any potential loss in the level of vaccine-induced protection due to immune escape (mismatching between the variant and the virus strain used to develop the vaccine). Booster vaccination for children and young people aged 12 to 17 years constitutes a secondary extension of those response measures.

Increasing age is very strongly associated with increasing risk from serious COVID-19 (hospitalisation and deaths). Therefore, where there are constraints in vaccine supply or vaccine deployment capacity, prioritisation by age is appropriate. Persons with underlying health conditions that place them in a COVID-19 clinical risk group should also be prioritised. Broadly, persons aged 12 to 15 years who are in a clinical risk group are at higher risk from serious COVID-19 than persons aged 16 to 17 years who are not in a clinical risk group. Where appropriate, deployment teams may wish to take these factors into account for operational purposes.

Key evidence considered

Risk of myocarditis following vaccination

Risk of myocarditis following infection

Vaccine efficacy and effectiveness against infection, symptomatic disease, hospitalisation and mortality

Risk of symptomatic disease, hospital admission, PICU admission, and mortality:

Long COVID

PIMS-TS